When the user of a mobile device (e.g., a cell phone) does not answer an incoming call, or when the calling party disconnects the call before the user can answer, the user receives a “missed call” or a similar indicator. The “missed call” feature tracks and reports to the user information related to the unanswered calls. However, to detect such missed calls, the user's mobile device must be powered on and be within the service coverage area of a servicing mobile network when the incoming call is received.
If the user's mobile device is powered off or if the user's mobile device is outside of the service coverage area, the user does not receive a missed call notification or any such indicator to let her know that she received a call from the calling party. In such scenarios, where the user's mobile device is unreachable, the incoming call is forwarded either to a voicemail account or to a call-forward number indicated by the user. The user would be aware that a call was received only when, for example, the calling party leaves a voicemail or when someone answers the call at the call-forwarded leg.
Certain calls, where the calling party abandons (i.e., disconnects) the call before depositing a voice mail (when the call is forwarded to a voicemail account) or before someone answers the call at the call-forwarded leg (when the call is forwarded to a call-forward number), are referred to herein as “slamdown” calls. In such situations, the user is not aware of any slamdown calls she may have received while her mobile device was unreachable.
To detect and report information related to calls received by an unreachable mobile device, prior art solutions utilize a trigger mechanism during the call-handling stage. Examples of such prior art solutions include U.S. patent application Ser. No. 10/448286 and U.S. patent application Ser. No. 08/883004. However, such prior art solutions are disadvantageous for at least the following reasons.
First, the prior art solutions detect and report any call that is forwarded to the user's voicemail or a call-forward number. The triggering mechanism used by the prior art solutions generates triggers (e.g., DP3 triggers) any time a call is deflected or forwarded to a voicemail account or a call-forward number. The trigger gets generated regardless of whether the user's mobile device is reachable or not. Therefore, in situations where the incoming call was forwarded when the user's mobile device was reachable (e.g., when the call was forwarded because the user did not answer the call), the user would unnecessarily receive multiple notifications of the same event. For example, the user would receive a first notification through the trigger mechanism, and a second notification through the regular “missed call” feature.
Second, the prior art solutions are incapable of detecting true slamdown calls. As discussed above, the prior art trigger mechanisms detect and report any call that is forwarded or deflected to a voicemail account or a call-forward number. However, if a calling party leaves a message (in the case of a voicemail account), or if someone answers the incoming call (in the case of a call-forwarded situation), the user would become cognizant of the identity of the calling party. Therefore, the user may consider an additional notification (from the triggering mechanism) superfluous or unnecessary in such non-slamdown calls because she is already aware of the calling party's identity.
Third, the triggering mechanism of the prior art solutions are number-based triggers. Such a triggering mechanism generates a trigger when the incoming call is forwarded to a specific number (e.g., a number associated with the voicemail account). If, for example, the operator of the mobile network uses multiple voicemail accounts, the operator would be encumbered with the burden of enabling the trigger for each number associated with the various voicemail accounts.
Fourth, the triggering mechanism of prior art solutions is generic to the entire mobile network. The prior art triggering mechanism, if implemented within the network, applies to all users of the network. The mechanism cannot be enabled specifically for targeted users, and cannot be linked to a user's subscription profile. Therefore, the operator would be unable to offer the call detect feature as a premium service to selected users of the mobile network.